The overall objective of the proposed investigation is to examine the feasibility of using lectins as toolsin microbial identification. To achieve this, initial studies will be directed toward elucidating the specificity of the agglutinin systems in our model, the horseshoe crab, Limulus polyphemus. Panels of bacterial antigens will be used to characterize the agglutinins present, employing standard Microtiter R techniques. The agglutinins will be purified using differential centrifugation as well as electrophoretic and chromatographic techniques. The molecular specificity of each agglutinin will be determined using hapten-inhibition assays. Finally, the uniformity of the agglutinin activity will be monitored both with the crab population under study and over a five-year time span. It is anticipated that the information derived from this investigation will form the basis for similar studies of other invertebrate-derived lectins.